Co-pending Patent application Ser. No. 07/760,438, filed Sep. 16, 1991, entitled "Print Scanner with Soft Key Variable Magnification," by K. A. Parulski et al, assigned to the assignee of the present application and the disclosure of which is herein incorporated, described a zoom/focus lens control mechanism for a high resolution color digitizing scanner, which enables the workload of the photofinisher, in particular the need for the photofinisher to perform a zoom lens adjustment for each photoprint of a given batch of photoprints to be scanned and digitized, to be substantially reduced.
Pursuant to the invention described in that application, by means of a set of frame, focus, program and capture control software routines, the magnification and focus default settings of the projection system's zoom lens may be readily recalibrated to new values associated with magnification and focus adjustments of the zoom lens, so as to allow the photofinisher to easily optimize the presentation of the photoprint image on a preview display monitor to which the output of the scanner's image sensor is coupled. After calibration, as additional photoprints of the same size of a batch are processed, the currently programmed default settings are used, without the need for adjustment, so that each photoprint will be properly imaged on the scanner's high resolution photosensor (e.g. a 1536.times.1024 pixel array yielding an approximately 1.6 Megapixel full frame count).
Such a lens control mechanism is especially useful in a photoprint scanner with is capable of automatically scanning a series of platen-mounted photoprints, the platens for which contain machine readable photoprint parameter information (e.g. bar codes or adjustable indicator elements), as described in co-pending U.S. patent application Ser. No. 07/760,437, filed Sep. 16, 1991, entitled "Photoprint Retaining Platen For Digitizing Image Scanner", by K. A. Parulski et al, assigned to the assignee of the present application and the disclosure of which is herein incorporated.
The photoprint scanner itself may be of the type described in co-pending U.S. patent application Ser. No. 07/762,323, filed Sep. 16, 1991, by K. A. Parulski et al, entitled "Dual Imaging Station Scanner", assigned to the assignee of the present application and the disclosure of which is also herein incorporated. Using the platen-mounted photoprint feature, this dual imaging station scanner is able to automatically digitize respective images contained on a plurality of sequentially fed, platen- mounted photoprints. The photoprints themselves may have been brought by the customer to the photofinisher in a loosely arrayed pile or mounted in a photo-album binder. The photoprint-mounting platens and platen feed station of the scanner allow a photofinisher to rapidly process any number of pictures provided by the customer, irrespective of the condition or form in which the photoprints are supplied. The machine-readable parameter information is detected by one or more image parameter sensors located in the platen feed path and is used to adjust the magnification and focus default settings of the scanner's image projection system, including zoom and focussing ring positions of the zoom lens, so as to facilitate the automatic processing of a plurality of photoprints of a common batch.
Within the photoprint image projection path of the scanner is an image projection device containing a variable magnification device in the form of an adjustable focus, zoom lens. The projection path is incident upon a photo-responsive device, such as a high resolution CCD sensor, image output signals from which are digitized for storage on a compact disc. Control of the operation of the scanner includes the use of the above-reference `preview` display device to which output signals provided by the photosensor are coupled so as to display a low resolution version of the image incident upon the high resolution CCD sensor to the photofinisher.
More particularly, in order to enable the photofinisher to optimally adjust the projection and focussing parameters of the scanner, such as any required adjustment of the zoom lens, a selected portion of the output of the high resolution (1536.times.1024 pixel) CCD image sensor is coupled separately of the high resolution image processing workstation to an auxiliary, lower resolution, monochromatic `preview` display unit, such as a 384.times.256 pixel array display unit. While it would be possible to use the high resolution color display terminal of the photofinishing workstation for this purpose, from a practical operational standpoint, the processing time it requires to display a full 6 Megapixel color frame (making use of an optical translation mechanism which effectively doubles the horizontal and vertical resolutions of the CCD sensor) is prohibitive. For successful operation of the scanner, what is necessary is that, prior to image capture, the photoprint be correctly positioned, and its image correctly sized and focussed on the image sensor. To satisfy these requirements, when `previewing` the image, the photofinisher does not need to view a full color image at its highest resolution; the job can be done quickly using a lower resolution, monochromatic display.